1. Field
This disclosure relates to test equipment for verifying performance of electric vehicle charging equipment.
2. Description of the Related Art
The Electric Vehicle Initiative has set a goal of 20 million electric vehicles on the road worldwide in 2020. In this patent, the term “plug-in electric vehicle”, or PEV, includes both battery-only electric vehicles and plug-in hybrid electric vehicles. Each of these vehicles will require access to a charging system to recharge the on-board battery. Electric Vehicle charging systems are termed Electric Vehicle Supply Equipment (EVSE), and sometimes referred to as an EV Charge Point (i.e. a location or point on a map where an electric vehicle may be recharged).
The global installed base of EVSEs may exceed, or soon will exceed, the number of electric vehicles. A large portion of these EVSEs are individual units installed in a vehicle-owner's home prior to taking delivery of the vehicle. Additional EVSE units are installed in commercial and industrial locations such as shopping malls, government facilities, business parks, and curbside in many municipalities that offer street parking.
The Society of Automotive Engineers (SAE) has defined an industry standard, SAE J1772™, that defines the charge coupler and electrical interfaces for 120V and 240V AC charging of a plug-in electric vehicle. This document also defines safety-related requirements on EVSEs including proximity detection contacts that tell both the EVSE and the PEV that the connector is connected properly and safely, electric signaling between the EVSE and the PEV to ensure the current drawn does not exceed either the installed circuit or the PEV's capabilities; and detection of ground faults and missing ground connections. IEC 61851-1 is similar specification covering EVSEs for use in Europe. Underwriters Laboratories has defined another industry standard, UL2231, to specify safety requirements for EVSEs.
Throughout this description, elements appearing in figures are assigned three-digit reference designators, where the most significant digit is the figure number where the element is introduced and the two least significant digits are specific to the element. An element that is not described in conjunction with a figure may be presumed to have the same characteristics and function as a previously-described element having the same reference designator.